EP0083027B1 - Improved stabilized staining solution producing a romanowsky effect and method of preparing it - Google Patents
Improved stabilized staining solution producing a romanowsky effect and method of preparing it Download PDFInfo
- Publication number
- EP0083027B1 EP0083027B1 EP82111631A EP82111631A EP0083027B1 EP 0083027 B1 EP0083027 B1 EP 0083027B1 EP 82111631 A EP82111631 A EP 82111631A EP 82111631 A EP82111631 A EP 82111631A EP 0083027 B1 EP0083027 B1 EP 0083027B1
- Authority
- EP
- European Patent Office
- Prior art keywords
- azure
- eosin
- solution
- percent
- amount
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
- 238000000034 method Methods 0.000 title claims description 10
- 239000012192 staining solution Substances 0.000 title claims description 6
- 230000000694 effects Effects 0.000 title description 5
- 239000000243 solution Substances 0.000 claims description 35
- SEACYXSIPDVVMV-UHFFFAOYSA-L eosin Y Chemical compound [Na+].[Na+].[O-]C(=O)C1=CC=CC=C1C1=C2C=C(Br)C(=O)C(Br)=C2OC2=C(Br)C([O-])=C(Br)C=C21 SEACYXSIPDVVMV-UHFFFAOYSA-L 0.000 claims description 32
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 claims description 24
- 239000000975 dye Substances 0.000 claims description 22
- CBPYOHALYYGNOE-UHFFFAOYSA-M potassium;3,5-dinitrobenzoate Chemical compound [K+].[O-]C(=O)C1=CC([N+]([O-])=O)=CC([N+]([O-])=O)=C1 CBPYOHALYYGNOE-UHFFFAOYSA-M 0.000 claims description 15
- 239000003381 stabilizer Substances 0.000 claims description 7
- 210000004369 blood Anatomy 0.000 claims description 6
- 239000008280 blood Substances 0.000 claims description 6
- 239000007795 chemical reaction product Substances 0.000 claims description 2
- 238000002360 preparation method Methods 0.000 claims 1
- CXKWCBBOMKCUKX-UHFFFAOYSA-M methylene blue Chemical compound [Cl-].C1=CC(N(C)C)=CC2=[S+]C3=CC(N(C)C)=CC=C3N=C21 CXKWCBBOMKCUKX-UHFFFAOYSA-M 0.000 description 19
- 229960000907 methylthioninium chloride Drugs 0.000 description 19
- 239000002244 precipitate Substances 0.000 description 11
- 238000010186 staining Methods 0.000 description 10
- 239000000203 mixture Substances 0.000 description 7
- 230000003647 oxidation Effects 0.000 description 6
- 238000007254 oxidation reaction Methods 0.000 description 6
- 239000000047 product Substances 0.000 description 6
- 230000015572 biosynthetic process Effects 0.000 description 4
- 238000001556 precipitation Methods 0.000 description 4
- YQGOJNYOYNNSMM-UHFFFAOYSA-N eosin Chemical compound [Na+].OC(=O)C1=CC=CC=C1C1=C2C=C(Br)C(=O)C(Br)=C2OC2=C(Br)C(O)=C(Br)C=C21 YQGOJNYOYNNSMM-UHFFFAOYSA-N 0.000 description 3
- 239000008187 granular material Substances 0.000 description 2
- 230000007774 longterm Effects 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- BWHMMNNQKKPAPP-UHFFFAOYSA-L potassium carbonate Chemical compound [K+].[K+].[O-]C([O-])=O BWHMMNNQKKPAPP-UHFFFAOYSA-L 0.000 description 2
- 230000035882 stress Effects 0.000 description 2
- PLXMOAALOJOTIY-FPTXNFDTSA-N Aesculin Natural products OC[C@@H]1[C@@H](O)[C@H](O)[C@@H](O)[C@H](O)[C@H]1Oc2cc3C=CC(=O)Oc3cc2O PLXMOAALOJOTIY-FPTXNFDTSA-N 0.000 description 1
- 108010077544 Chromatin Proteins 0.000 description 1
- 230000032683 aging Effects 0.000 description 1
- 150000003973 alkyl amines Chemical class 0.000 description 1
- 125000000129 anionic group Chemical group 0.000 description 1
- 238000009835 boiling Methods 0.000 description 1
- 210000001185 bone marrow Anatomy 0.000 description 1
- 235000012730 carminic acid Nutrition 0.000 description 1
- 125000002091 cationic group Chemical group 0.000 description 1
- 210000004027 cell Anatomy 0.000 description 1
- 210000003850 cellular structure Anatomy 0.000 description 1
- 239000013626 chemical specie Substances 0.000 description 1
- 210000003483 chromatin Anatomy 0.000 description 1
- 230000008645 cold stress Effects 0.000 description 1
- 238000011109 contamination Methods 0.000 description 1
- 230000018109 developmental process Effects 0.000 description 1
- 238000001914 filtration Methods 0.000 description 1
- GNBHRKFJIUUOQI-UHFFFAOYSA-N fluorescein Chemical class O1C(=O)C2=CC=CC=C2C21C1=CC=C(O)C=C1OC1=CC(O)=CC=C21 GNBHRKFJIUUOQI-UHFFFAOYSA-N 0.000 description 1
- 238000009472 formulation Methods 0.000 description 1
- 208000014951 hematologic disease Diseases 0.000 description 1
- 210000003630 histaminocyte Anatomy 0.000 description 1
- 230000001744 histochemical effect Effects 0.000 description 1
- 230000003993 interaction Effects 0.000 description 1
- 150000002500 ions Chemical class 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 238000002156 mixing Methods 0.000 description 1
- 230000000877 morphologic effect Effects 0.000 description 1
- 210000000440 neutrophil Anatomy 0.000 description 1
- 210000004940 nucleus Anatomy 0.000 description 1
- 230000003071 parasitic effect Effects 0.000 description 1
- 229910000027 potassium carbonate Inorganic materials 0.000 description 1
- 239000000843 powder Substances 0.000 description 1
- 230000002035 prolonged effect Effects 0.000 description 1
- 150000003839 salts Chemical class 0.000 description 1
- 230000035939 shock Effects 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 230000006641 stabilisation Effects 0.000 description 1
- 238000011105 stabilization Methods 0.000 description 1
- 230000000087 stabilizing effect Effects 0.000 description 1
- 239000007858 starting material Substances 0.000 description 1
- 239000011550 stock solution Substances 0.000 description 1
- 239000001016 thiazine dye Substances 0.000 description 1
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N1/00—Sampling; Preparing specimens for investigation
- G01N1/28—Preparing specimens for investigation including physical details of (bio-)chemical methods covered elsewhere, e.g. G01N33/50, C12Q
- G01N1/30—Staining; Impregnating ; Fixation; Dehydration; Multistep processes for preparing samples of tissue, cell or nucleic acid material and the like for analysis
Definitions
- Stains comprising mixtures of Methylene Blue and related thiazine dyes with Eosin are used routinely for the coloration of blood and bone- marrow films.
- Those Romanowsky-type stains demonstrate the morphological features which distinguish the various haemopietic cells and those which characterize blood diseases.
- the term Romanowsky-type stain is commonly applied to any stain comprising Methylene Blue, its products of oxidation and a halogenated Fluorescein dye, usually Eosin Y.
- Successful Romanowsky-type stains produce the Romanowsky effect. This may be defined as the condition in which the typical coloration of certain cell components results from the combined action of a cationic and anionic dye, and cannot be produced by either dye acting alone.
- Azure B and Eosin Y are very soluble in methanol individually. However, a mixture of Azure B and Eosin Y in methanol produces a heavy precipitate within a few hours at ambient temperature. Thus, while a fresh mixture of solutions of the two dyes provides satisfactory performance on blood smears, the useful shelf-life of the solution is severely limited.
- the amount of Eosin Y dissolved in methanol will range from 0.062 to 0.104 percent on a weight/volume basis (WN) and preferably from 0.078 to 0.088 percent.
- the concentration of Azure B is typically from 0.032 to 0.080 percent (WN) with a concentration of from 0.043 to 0.047 percent being preferred.
- the ratio of Eosin Y to Azure B should be from 2.05:1 to 1.66:1 on a dry weight basis.
- the amount of diethylamine hydrochloride employed is a stabilizing amount; i.e. that amount which will significantly reduce their precipitation when the dyes are placed in methanol solution. We prefer to employ an amount of diethylamine hydrochloride equal to from 0.24 to 0.64 percent of the stain solution on a weight/volume basis.
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- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Engineering & Computer Science (AREA)
- Biomedical Technology (AREA)
- Molecular Biology (AREA)
- Physics & Mathematics (AREA)
- Chemical & Material Sciences (AREA)
- Analytical Chemistry (AREA)
- Biochemistry (AREA)
- General Health & Medical Sciences (AREA)
- General Physics & Mathematics (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Investigating Or Analysing Biological Materials (AREA)
- Sampling And Sample Adjustment (AREA)
Description
- Stains comprising mixtures of Methylene Blue and related thiazine dyes with Eosin are used routinely for the coloration of blood and bone- marrow films. Those Romanowsky-type stains demonstrate the morphological features which distinguish the various haemopietic cells and those which characterize blood diseases. The term Romanowsky-type stain is commonly applied to any stain comprising Methylene Blue, its products of oxidation and a halogenated Fluorescein dye, usually Eosin Y. Successful Romanowsky-type stains produce the Romanowsky effect. This may be defined as the condition in which the typical coloration of certain cell components results from the combined action of a cationic and anionic dye, and cannot be produced by either dye acting alone. It consists of the purple coloration of leucocyte chromatin and neutrophil granules and the magenta or carmine coloration of the nuclei of parasitic Protozoa. This'effecUs described as the result of some interaction of Azure B (an oxidation product of Methylene Blue) and Eosin Y by P. N. Marshall in his review of Romanowsky-type Stains in Haemotology appearing in Histochemical Journal 10 (1978) Pp. 1-29. This article also describes the phenomena of ageing the dye to cause it to stain mast cell granules red and the theory that Methylene Blue ages in solution to give some new dye which produces the proper staining. The requirement that the dye be aged was circumvented by boiling a solution of Methylene Blue with potassium carbonate to provide what became known as polychrome Methylene Blue. Wright's stain, extensively used in the United States, is a Romanowsky stain solution in which the Methylene Blue is polychromed by one or more known techniques and the product then mixed with Eosin Y. Polychroming results in a complex mixture of dyes including Azures B, C and A as well as leaving some Methylene Blue starting material in the final mixture. Marshall reports two disadvantages inherent in the polychroming of Methylene Blue. One is that the procedure results not only in the production of dyes essential for Romanowsky-type staining, but also in certain extraneous ones. He also states that the stain is not suitable for reproducible production on a commercial scale because polychroming cannot be effectively controlled on such a scale. The Marshall article reports the recent development of a reproducible stain suitable for commercial exploration, which avoids the polychroming process being comprised of purified Azure B and commercial Eosin Y whose methanolic stock solutions are prepared separately and mixed just prior to staining. These dye solutions are prepared separately and mixed just prior to use because the admixture of solutions of Azure B and Eosin Y results in the rapid formation of a precipitate which quickly renders the stain unsuitable for the intended purpose. It also appears that, in the typical Romanowsky-type stain, the Methylene Blue slowly oxidizes to Azure B and that the combination of Azure B and Eosin Y accounts for the desirable staining properties. The oxidation process will also continue in a sequence which will form other azure products that are not essential for staining but reduce the Azure B concentration. the Azure B formed by the gradual oxidation will form a reaction product with Eosin Y which precipitates from solution, but this precipitation is not as catastrophic as when Azure B and Eosin Y are combined directly in solution because of the gradual oxidation of Methylene Blue to Azure B. It would be desirable to provide a stabilized solution of Azure B and Eosin Y which would exhibit a reasonable shelf-life in order to avoid the step of mixing the separate solutions just before their use. U.S. Patent 4,290,769, issued September 22, 1981, discloses the stabilization of a Romanowsky-type stain solution comprising Methylene Blue, polychromed Methylene Blue products (azures) and an eosin dye with an alkylamine hydrohalide. Diethylamine hydrochloride is described as being a useful stabilizer for this three- component polychromed stain system. Unexpectedly, we have discovered that diethylamine hydrochloride is a suitable stabilizer for the much more unstable two-component system of Azure B and Eosin Y in methanolic solution.
- The present invention is a stabilized blood staining solution consisting essentially of a methanolic solution of dyestuff, consisting of Azure B and Eosin Y, characterized in that it contains diethylamine hydrochloride as a stabilizer.
- Azure B and Eosin Y are very soluble in methanol individually. However, a mixture of Azure B and Eosin Y in methanol produces a heavy precipitate within a few hours at ambient temperature. Thus, while a fresh mixture of solutions of the two dyes provides satisfactory performance on blood smears, the useful shelf-life of the solution is severely limited.
- In preparing the stain solution of the present invention, we prefer to combine the Eosin Y with the diethylamine hydrochloride before introducing Azure B to the methanol solution. This is the case because we believe the diethylamine hydrochloride interacts with the Eosin Y to form a chemical species which does not react with Azure B to form a precipitate. Upon addition of Azure B to the solution, no rapid precipitation is observed, and the solution provides an excellent Romanowsky staining effect.
- In a typical stain solution, the amount of Eosin Y dissolved in methanol will range from 0.062 to 0.104 percent on a weight/volume basis (WN) and preferably from 0.078 to 0.088 percent. The concentration of Azure B is typically from 0.032 to 0.080 percent (WN) with a concentration of from 0.043 to 0.047 percent being preferred. For best staining results, the ratio of Eosin Y to Azure B should be from 2.05:1 to 1.66:1 on a dry weight basis. The amount of diethylamine hydrochloride employed is a stabilizing amount; i.e. that amount which will significantly reduce their precipitation when the dyes are placed in methanol solution. We prefer to employ an amount of diethylamine hydrochloride equal to from 0.24 to 0.64 percent of the stain solution on a weight/volume basis.
- The method of practicing the invention is further illustrated by the following example:
- Diethylamine hydrochloride, 11.52 g (0.48% WN) and Eosin Y, 2.11 g (0.0879% WN), were mixed thoroughly with 2.4 liters of methanol for 20 minutes. After holding overnight (16 hours) at ambient temperature, Azure B, 1768 g (0.074% WN), was introduced. The solution was mixed thoroughly for 20 minutes and then held at ambient temperature for several hours before filtration to remove any solids. The component stain solution was found to produce a Romanowsky-type effect as indicated by the performance data in Table I.
- No precipitate was observed for more than two months at 23°C, 40°C and 50°C stability stress. However, this stain solution did form a small amount of precipitate after storage at 5°C for 20 days, so prolonged cold storage should be avoided.
- The combination of Eosin Y and Azure B in methanol resulted in catastrophic precipitation; i.e. the precipitate began forming immediately and continued to form to the extent that within 2 to 3 hours the solution contained insufficient stain for proper blood staining effects which prohibited further work with the unstabilized solution.
- The stain disclosed herein is not classified as a Romanowsky-type stain because Methylene Blue is present in all such stains. Although Methylene Blue is not an essential component for staining, it is very similar in structure to Azure B and is considered to be a contributing factor in formation of the 1:2 ion pair of Eosin Y: blue component. A conventional polychromed Romanowsky-type stain is relatively more stable than the stain solutions comprising only Eosin Y and Azure B under cold stress. Conventional polychromed stain solutions without the stabilizer, diethylamine hydrochloride, produced precipitate at 5°C after about 50 days of stress. It appears that Methylene Blue may behave as a secondary system stabilizer in a conventional polychromed stain to retard but not eliminate precipitate formation. Since the typical Romanowsky-type stain comprising three dyes; i.e. an azure, Methylene Blue and an eosin, is somewhat more stable than that containing only Azure B and Eosin Y it, therefore, must be stabilized only for long-term storage as described in aforementioned U.S. Patent 4,290,769. Since Methylene Blue itself serves as a stabilizer which will retard but not eliminate precipitate formation, it was unexpected that diethylamine hydrochloride would stabilize the two dye, Azure B/Eosin Y, system. The three dye system is still preferred when long-term stability is required since during cold shock tests it did not produce substantial precipitate for 50 days at 5°C. However, there are advantages to use of the stabilized two dye system when shorter term stability is satisfactory since the problems associated with the use of polychromed Methylene Blue are eliminated. For example, conventional stain formulations utilizing polychromed dye powder are found to have significant batch- to-batch performance variations because of non- reproducible dye composition, i.e. Azure B and numerous other oxidation products, and metal salt contamination which causes de-staining. The avoidance of polychromed dye and use ot individual pure dye components eliminates these problems.
Claims (8)
1. A blood staining solution consisting essentially of a methanolic solution of dyestuff, consisting of Azure B and Eosin Y, characterized in that it' . contains diethylamine hydrochloride as a stabilizer.
2. A solution according to claim 1, characterized in that the amount of Eosin Y is from 0.062 to 0.104 percent, the amount of Azure B is from 0.032 to 0.080 percent and the amount of diethylamine hydrochloride is from 0.24 to 0.64 percent of the stain solution, on a weight/volume basis.
3. A solution according to claim 1 or 2, characterized in that the amount of Eosin Y is from 0.078 to 0.088 percent and the amount of Azure B is from 0.043 to 0.047 percent.
4. A solution according to any of claims 1 to 3, characterized in that the ratio of Eosin Y to Azure B is from 2.05:1 to 1.66:1 on a dry weight basis.
5. A method for the preparation of a blood staining solution, characterized in that it comprises combining Eosin Y and diethylamine hydrochloride in methanol to form their methanolic solution and then adding Azure B to the solution to form a stabilized staining solution consisting essentially of the reaction product of Eosin Y and diethylamine hydrochloride and Azure B.
6. A method according to claim 5, characterized in that the amount of Eosin Y is from 0.062 to 0.104 percent, the amount of Azure B is from 0.032 to 0.080 percent and the amount of diethylamine hydrochloride is from 0.24 to 0.64 percent of the staining solution, on a weight/volume basis.
7. A method according to claim 5 or 6, characterized in that the amount of Eosin Y is from 0.078 to 0.088 percent and the amount of Azure B is from 0.043 to 0.047 percent.
8. A method according to any of claims 5 to 7, characterized in that the ratio of Eosin Y to Azure B is from 2.05:1 to 1.66:1 on a dry weight basis.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US06/335,227 US4363632A (en) | 1981-12-28 | 1981-12-28 | Stabilized solution producing a Romanowsky effect |
| US335227 | 1981-12-28 |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| EP0083027A1 EP0083027A1 (en) | 1983-07-06 |
| EP0083027B1 true EP0083027B1 (en) | 1985-09-11 |
Family
ID=23310819
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| EP82111631A Expired EP0083027B1 (en) | 1981-12-28 | 1982-12-15 | Improved stabilized staining solution producing a romanowsky effect and method of preparing it |
Country Status (7)
| Country | Link |
|---|---|
| US (1) | US4363632A (en) |
| EP (1) | EP0083027B1 (en) |
| JP (1) | JPS5951351A (en) |
| AU (1) | AU532828B2 (en) |
| CA (1) | CA1167750A (en) |
| DE (1) | DE3266245D1 (en) |
| ES (1) | ES8402608A1 (en) |
Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4392864A (en) * | 1982-02-01 | 1983-07-12 | Miles Laboratories, Inc. | Stabilized Romanowsky stain solution |
| DE3533515A1 (en) * | 1985-09-20 | 1987-04-02 | Merck Patent Gmbh | STABILIZER FOR COLOR SOLUTIONS |
| US4816244A (en) * | 1986-02-14 | 1989-03-28 | Sigma Chemical Company | Stabilized stain solutions containing aliphatic and aromatic alcohols |
| US6858432B2 (en) * | 2002-08-29 | 2005-02-22 | Wescor, Inc. | Method and staining reagent for staining hematology sample in an automated staining apparatus |
| CN103874913B (en) * | 2011-06-17 | 2017-04-26 | 罗氏血液诊断股份有限公司 | Solutions for histoprocessing of biological samples |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4290769A (en) * | 1980-10-14 | 1981-09-22 | Miles Laboratories, Inc. | Stabilized Romanowsky stain solution |
| DE3620146A1 (en) * | 1986-06-14 | 1987-12-17 | Zeiss Carl Fa | METHOD FOR TESTING COMPONENTS MADE OF TRANSPARENT MATERIAL FOR SURFACE DEFECTS AND INCLUDES |
-
1981
- 1981-12-28 US US06/335,227 patent/US4363632A/en not_active Expired - Lifetime
-
1982
- 1982-08-26 CA CA000410172A patent/CA1167750A/en not_active Expired
- 1982-08-30 AU AU87839/82A patent/AU532828B2/en not_active Ceased
- 1982-12-15 DE DE8282111631T patent/DE3266245D1/en not_active Expired
- 1982-12-15 EP EP82111631A patent/EP0083027B1/en not_active Expired
- 1982-12-22 JP JP57224052A patent/JPS5951351A/en active Granted
- 1982-12-28 ES ES518621A patent/ES8402608A1/en not_active Expired
Non-Patent Citations (1)
| Title |
|---|
| P.N. Marshall, Histochemical Journal, 10. (1978) pp. 1-29 * |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS5951351A (en) | 1984-03-24 |
| JPH0151143B2 (en) | 1989-11-01 |
| ES518621A0 (en) | 1984-02-01 |
| AU8783982A (en) | 1983-07-07 |
| ES8402608A1 (en) | 1984-02-01 |
| US4363632A (en) | 1982-12-14 |
| CA1167750A (en) | 1984-05-22 |
| DE3266245D1 (en) | 1985-10-17 |
| EP0083027A1 (en) | 1983-07-06 |
| AU532828B2 (en) | 1983-10-13 |
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